Want to Export content of certain node-types as XML

Hi,

I've got a custom node type "biography" that contains information about my site members. I'm trying to set up a system whereby someone can export the contents of those biography nodes as XML where each field in my node type is tagged using the computer readable name of that field.

For example:

I've got very little PHP and XML experience, but I'm willing to learn. What I'm hoping for are some suggestions of modules and or concepts I should be looking into. Suggested reading is also appreciated.

thank you kindly,

Adam